Treadle-actuated mechanism



June, 1929. G, JULIA 1,7l6g586 TREADLE ACTUATED MECHANISM Filed Aug. 4. 1920 2 Sheets-Sheet 1 min/95s Filed Aug. 4. 1920 2 Sheets-Sheet 2 Patented June ll, i929.

lJNlTElE STATEfi are GIDEON JULIAN, OF BEVERLY, MASSACHUSETTE), A'SSEGNOR TO UNITED SHOE IMA- CHINERY COBP OBATION, OF PATERSON, NEW JERSEY, A'COBPOBA'IION OF NEW JERSEY.

LBEADLE-AGTUATED MECHANISM.

Application filed August .4, 1920.

This invention relates to treadle mechanisms, and more particularly to treadle mechanisms for actuating work holding or pressure applying devices. The invention is herein illustrated in its application to a shoe sole rounding machine for the purpose of actuating the work holding clamp, but it is to be understood that the novel features of the invention are not limited in respect to the particular character of the machine in which it is illustrated.

In various types of machines such as stockfitting machines for boot and shoe soles, which are provided with clamping or pre sure applying devices, these devices are normally maintained in open or inoperative positions and it is desirable relatively to actuate the pressure applying members by a single movement of a treadle so as first to close them upon the work and thereafter to cause them to apply pressure to the work. Shoe sole rounding machines for example, are provided with a stationary pattern for supporting the sole blank that is to be operated upon, a work holding clamp which is normally raised above the supporting pattern to permit the work to be readily placed upon the latter, and treadle mechanism actuated by a single depression of a foot'treadle to bring the clamp into engagement with the work and then to apply suificient pressure to the work to hold it securely forthe sole rounding operation.

One object ofthe present invention is to provide an improved treadle'mechanism' of the above-named general character which may be operated by comparatively light pressure and with a minimum amount of movement of the treadle.

lVith this object in view, the illustrated embodiment of the invention is provided with treadle operated mechanism, for actuating a clamping device to apply pressure to work, comprising means actuated directly by the treadle for yieldingly imparting a preliminary or closing movement to. the clamping device to bring it into engagement with the work, and other means also actuatet directly by the treadle and co-operating with a portion of the first-named means to impart positively an additional movement to the clamping device to clamp the work firmly against the work support. As herein illustrated, the clamp operating mechanism comprises toggle links one of which Serial N0. 401,126.

is extensible and consists of an upper member connected with the work clamp .and a lower member arranged to slide relatively to the upper member during the preliminary movement of the clamp but to be connected rigidly with the upper member throughout the application of the clamping pressure. The other illustrated toggle link consists of a lever having a relatively short arm directly connected with the lower member of the extensible toggle link, and a relatively long arm yieldingly connected, through an auxiliary lifting rod and spring'surrounding it, with the upper member of the extensible link. Because of the difference in length and the angular relation of the long and short lever arms the auxiliary lifting rod operates at a faster rate to-bring the clamp into engagement with the work than does the toggle to clamp the work securely and consequently the total amount of movement which it is necessary for the operator to impart to the treadle is materially less than in machines heretofore employed. Furthermore, the po sitions of the treadle and the'toggle members are'such when the actual pressure is applied to the work that a considerably lighter pressure need be applied to the treadle by the operator than in machines provided with the usual toggle operated clamp mechanism.

The invention further consists in the fea- ;tures of construction and combinations of parts hereinafter described and particularly pointed out in the appendedclaims, the advantages of which will be apparent to those skilled in the art.

The various features of the invention will bebest understood from a description of the preferred embodiment thereof, illustrated in the accompanying drawings, in which the invention is shown as embodied in a sole rounding machine such as that disclosed in United States Letters Patent No. 882,009, granted March 17 1908, to Benjamin F. Mayo, and assigned to United Shoe Machinery Corporation.

In the drawings, Figure 1 is a view, in side elevation, of the machine of said prior patent showing the improved treadle mechanism constituting thepresent invention embodied therein, certain parts of the machine being broken away, and a portion of the frame being shown in vertical section todisclose parts of said, mechanism otherwise hidden from view; Fig. 2 is a plan view,

- rounding operation, the material to be operated upon is held in position on the pattern 8 by'means of a clamp 14 carried by a block 16 pivotally secured to the lower end of a slide 18 which is mounted in an overhanging portion 20 of the machine frame. The slide 18 is connected to one arm of a lever 22 which is fulcrumed upon a stud 24 supported by said portion 20 of the machine frame, and is adapted to actuate the slide 18 to force the clamp 14 toward the pattern or to retract it therefrom. he path of movement imparted to the clamp 14 may be varied by means of an adiustable connection between the slide 18 and the lever 22. This connection consists of a rod 26 provided with right and left screw threads having a screw threaded engagement with pins or blocks 28 and 30 pivotally mounted upon the lever 22 and slide 18, respectively.

The parts of the machine above described are constructed and arranged in substan-.

tially the samemanner as the corresponding parts of the machine of said prior patent,

the various features of the present invention being embodied in the treadle mechanism for actuating the lever 22 to operate the clamp 14, and which will now be described.

The treadle mechanism comprises a toggle consisting of apair oftoggle members 34 and 36 and a foot treadle 3 8 by means of which the toggle is operated to swing the Cir the machine.

lever 22. The upper toggle member 34 comprises an extensible link, the upper end of which is pivoted at 40 to the rear extremity of the lever 22. The lower toggle member 36 comprises a three-armed lever which is fulcrumed on a pivot stud 42 that is supported at its opposite ends in the frame of The lower extremity of the upper toggle member 34 is connected by means of a knuckle pivot 44 with the uppermost arm 46 of the lower toggle member36. The foot treadle 38 is fulcrumed on a hori' zontal pivot stud 48, the opposite ends of which are supported by the upwardly projecting ears of a bracket 50 which is secured to the base of the machine frame. The treadle 38 is extended rearwardly beyond the pivot stud 48, asindicated at 52, and said rearward extension is connected by means of a short vertical rod 54 with the ber 86. The arm 56 extends substantially at right angles to the arm 46 so that said arms constitute, in effect, a bell-crank lever. The opposite ends of the connecting rod 54 are loosely received in cup-shaped sockets formed in the corresponding ends of the arm 56 and the rearward extension 52 of the treadle 38. The work clamp 14 is normally held in its raised or open position, as indicated in Fig. 1, by means of a coiled spring one end of which is secured to the arm 56 and the opposite end thereof to a lug on the bracket 50, the force of the spring tending to break the toggle 3436 and normally holding the treadle 38 in its raised position.

It is obvious that if the upper toggle mem ber 34 consisted of an integral link, the straightening of the toggle 34-36, upon the depression of the treadle 38, would oper- .ate to lower the clamp 14 into engagement with the work and then to clamp the work against the pattern 8. It is desirable, however, in order to lessen the work of the operator, materially to reduce the distance through which the treadle has to be depressed to actuate the work clamp 14. Accordingly provision is made for increasing the lifting effect of the toggle 3436 throughout the greaer part of its straightening movement so that the lever 22 and clamp 14 will move more rapidly while the latter is being lowered into engagement with the work than while it is actually compressing the work, thus causing said lever to be swung through a greater distance than it could. be moved by the action of the toggle in the same time. To this end the lower portion ofthetoggle member 34 is composed of two relatively movable parts, an outer sleeve 60, the lower end of which is connected to the toggle member ,36 by the pivot 44, and an inner telescoping rod 62 which is indirectly connected to the lever 22 by the pivot 40 and is. adapted to slide freely within the sleeve 60. The rod 62 is adapted to be actu ated independently of the sleeve by means of an auxiliary lifting rod 64 (Fig. 4) which is connected with the central arm 66 of the toggle member 36, said arm being longer than the arm 46 and arranged'in such an angular position with relation thereto that when the treadleis depressed the rod 62 will be raised at a higher rate of speed than that at which thesleeve 60 is raised. As shown in Figs. 4 and 5, the upper end of the auxiliary lifting rod 64 is pivoted at 68 to a;

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opposite sides of a yoke that is formed at the outer end of the central arm 66. Upward movement of the central arm 66 is transmitted yieldingly to the lifting rod 64 and to the rod 62 through a spring which is coiled around the rod 64 between a shoulder 82 at the upper end of the rod and a flattened face 84 that is formed on the ,upper side of the block 78; In order that the rod 62 may be positively moved in a downward direction to raise the clamp 14 from the work, the auxiliary lifting rod 64 is provided with an adjustable stop 86 consisting of a collar which surrounds said rod, the upper end of the collar being adapted to engage a fiattened face 88 on the underside of the block 78 and the collar being confined between the block and an adjusting nut 90 which is screw-threaded upon the lower extremity of the rod 64. A look nut 92 is provided for securing the nut 90 in adjusted position on the rod 64. By employing the collar 86 between the nut 90 and the block 78, the nuts 90 and 92 are located as shown in Fig. 4, where they may be conveniently engaged by a wrench for the purpose of varying their position on the rod 64.

lVith the above described construction, both the sleeve 60 and the rod 62 forming the upper toggle member 34, are raised by the depression of the treadle and the resulting rocking of the toggle member 36, but the rod 62 is raised at a higher rate of speed than the sleeve 60 by reason of the difference in length and angular position of the arms 66 and 46 of said lower toggle member 36. Consequently, the clamp 14 is brought into engagement with the work by the depression of the treadle through a considerably less distance than if a mere straightening of the toggle 34-36 was relied upon to lower the clamp.

After the clamp 14 has been brought into engagement with the work, considerable pressure must be applied to the clamp in order to hold the work firmly for the sole rounding or other operation thereon. The application of the clamping pressure to the clam J is effected by the toggle 3436 during the nal portion of its straightening movement. To permit the application of the pressure to the clamp by means of said toggle, provision is made for connecting together the rod 62 and the sleeve. 60 upon the engagement of the clamp 14 with the work so that the rod 62 will thereafter be raised by the arm 46 with the sleeve 60, while the spring 80 yields to take up the excess upward movement of the central arm 66. The means for connecting the rod 62 and the sleeve 60 so that the upward movement of the sleeve will be transmitted to the rod comprises a lifting pawl 96 (Fig. which is pivoted at 98 between a pair of ears at one side of the sleeve. The pawl 96 projects into a longitudinal slot 100 in the wall of the sleeve 60 and is adapted to engage rack teeth 102 formed upon a rack bar 104 which is secured to the rod 62 by means of screws 106. During the work engaging movement of the work clamp the lifting pawl 96 is disengaged from the rack teeth 102 as shown in Fig. 4. To enable the pawl 96 to swing into engagei'nent'with the rack teeth 102 after the clamp has engaged the work, the pawl is connected in the following manner with the central arm 66 of the toggle member 36. Extending from the pawl 96 is a tail 108 which is connected by means of a pair of links 110, severally arranged on opposite. sides of the sleeve 60, with the 'up per end of an arm 112 that is pivoted at its lower end on a. stud 114 supported by a yoke 116 longitudinally offset from the bracket 70. A second arm 118 is also pivot-ed upon the stud 114, the bifurcated upper end of said arm straddling the arm 112 and being interposed between the latter and the opposite sides of the yoke 116 (Fig. 5). The arms 112 and'118 are normally maintained substantially at right angles to each other by means of a spring 120 the ends of which are seated in two socketed projections 1'22 and 124 on the arms 112 and 118, respectively, the spring tending to hold a portion of the arm 118 against a stop lug 126 on the opposite sides of the forked portion of the link being pivoted to the arm by a stud 132 which extends through the arm at a point adjacent the sockets 7 9. After the clamp 14 has been brought into engagement with the work, the rod 62 will no longer be lifted by the action of the arm 66 and continued upward movement of said arm relatively to the rod 62 will be taken up by the spring 80. The arm 66, however, continues to move upwardly relatively to the pivot stud 114 and this movement causes the bell-crank lever arms 112 and 118 to be rocked in a direction to swing the pawl 96 into engagement with the teeth on the rod 62. After the pawl 96 has engaged the teeth on the rod 62 the continued straightening of the toggle members 3436 causes pressure to be applied to the work by the work clamp 14. Hence, during further depression of the treadle after the clamp has engaged the work, the clamping pressure is increased proportionally with the depression of the spring 80 until the pawl 96' engages the rack 102. At this instant, the toggle 4662 starts to operate and because of the relatively short length of the arm 46 and the more nearly alined position of the toggle links 4662, the clamping pressure is abruptly increased when the pawl 96 engages the rack 102 to render the toggle 46-62 'eflective and the toggle 66-62 ineffective to operate the clamping mechanism. During this period the movement of the central arm 66 of the lower toggle member 36, relatively to the pivot stud 114, is taken up by the spring 120, the latter permitting the arm 118 to swing upwardly relatively to the arm 112, thus maintaining pressure on the pawl 96 to keep it in engagement with therack 102. In order that the straightening movement of the toggle may be arrested before the knuckle pivot 44 reaches dead center the downward movement of the treadle 38 is limited by means of an adjustable stop pin 136 (Fig. 1) whicl is adapted to be engaged by the base of a recess 138 in the under side or the treadle.

The normal position of the work clam above the pattern 8 may be adjusted by means of the rod 26 in accordance with the thickness of the work to be operated upon, as hereinbefore described, so that when the clamp has been lowered into engagement with the work the toggle members will be properly positioned to cause the required degree of pressure to be imparted to the work by the remaining portion of the downward movement of the foot treadle. In order to insure the application 01": an equal amount of pressure to the work, at each eration of the machine, in cases where the work clamp is improperly adjusted so that it is normally positioned too close to the pattern for the thickness of the sole to be operated upon, a yielding connection is provided between the rod 62 and the lever 22. To this end a rod 140 (Fig. 1) of smaller diameter than the rod 62 is screw-threaded into theupper end of said latter rod and V telescopes within a sleeve 142, the upper end longitudinal movement of said rod and sleeve. A still coiled spring 148 surrounds the lower portion of the rod 140 between the upper end of the rod 62 and the lower end of the sleeve 142. The strength of the spring 148 is such that under normal conditions it will not be compressed to any substantial extent by the straightening of the toggle 3436 to apply pressure to the work clamp 14. If, however, the work clamp 14 is adjusted too close to the pattern 8 for the thickness of the material which is to be op.- erated upon, the spring 148 will yield to permit the completion of the movements ot the treadle and toggle members.

By means of the above described toggle mec anism a heavy clamping pressure may be exerted upon the work by the application, by the operator, of a considerably lighter pressure to the treadle than has heretofore been necessary effectively to operate the work clamp in machines of the type herein described. Consequently, machines provided with the present improved tr'eadle mech anism may be readily operated by women operatives who would not have sufficient strength to operate such machines repeatedly when equipped with ordinary treadle mechanism. Furthermore, by reason of the employment of the extensible toggle link and the auxiliary lifting rod 64, the amount of movement which the operator must impart to the treadle is materially less than in prior machines of the type referred to.

Upon the release of the treadle 38 the work clamp and the treadle are returned to their normal positions by the spring 58. It will be seen that as the toggle 3436 begins to break under the influence otthe spring 58 the sleeve 60 will start to descend immediately whereas the rod 62 will not start to move downward until the compression of the spring has been relieved and the block 78 has beenr'eturned into engagement with the stop collar 86. Thedownward movement of the sleeve 60 relatively to the rod 62 causes the lifting pawl 96 to be lowered bodily sutficientaly to retract its upper end from the shoulder of the rack tooth which it engaged so that the pawl will. be free to swing outwardly after the block 78 has engaged the stop collar 86 and the arm 118 has been swung downwardlyagainst the stop lug 126 so that the arm 112 is rocked in unison with the arm 118. The downward swinging movement of the arm 112 is communicated through the links 110 to the pawl 96, re-

storing the latter to its normal retracted po- ."treadle it hit by a heavy moving object, the

treadle is constructed of front and rear sections or members, the rear member being pivotally iounted on the bracket 50 as hereinbefore described and the front member being normally maintained in longitudinal alinement with the rear member but adapted to yield laterally in response to any sidewise pressure thereagainst. To this end the front treadle member is pivoted upon a vertical stud 150 (Figs. 1, 2 and 3) the opposite ends of which are supported in a yoke 152 which is formed upon the rear treadle member and embraces the pivoted end of of the machine.

said front member. The front treadle mem: her is normally maintained in alinement with the rear treadle member, as shown in Fig. 2, by means of a spring-pressed plunger 15% which is carried by the yoke 152 and engages a V-shaped notch 156 in the pivoted end of the front treadle member. The plunger 154 will be readily forced out of the notch 156 under unintentional sidewise pressure on the front trcadle member, permitting it to swing toward one side or the other of its normal central position. This construction further permits the lateral displacement of the front portion of the treadle to facilitate the removal of the chips produced. by the machine which collect around the base of the machine and also permits the front treadle' member to be moved against the frame so that the treadle will be less likely to be injured during shipment gagement with the sides of the recess 138 after the operator has started to depress the treadle, serves to prevent an undesired lateral displacement of the treadle while the t-readle mechanism is being operated.

lVhile it is preferred to employ the spe cific construction and arrangement of parts herein shown and described, it will be understood that this construction and arrangement is not essential except so far as specified in the claims and may be changed or modified without departing from the spirit and true scope of the invention.

What is claimed as new, is:

1. The combination with a work support and a work clamp for holding the work against the support, of clamp-operating mechanism comprising a treadle, means operated by the treadle for imparting a preliminary movement to the clamp to bring the clamp into engagement with the work, and other means co-operating with a portion of said first-named means and deriving motion solely from the treadle for imparting an additional movement to the clamp to clamp the work firmly against the support.

2. In a stock fitting machine, the combination of means for supporting a piece of work to be operated upon, a normally retracted work clamp, and mechanism for actuating the clamp comprising a treadle, a pair of toggle members actuated thereby for causing the clamp to apply pressure to the work, and auxiliary means cooperating with the toggle members for imparting a preliminary movement to the clamp tobring it into engagement with the work before pressure is appliedto the toggle. v

3. In a stock fitting machine, the combination of means for supporting a piece of work to be operated upon, a normally retracted work clamp, mechanism for actuating the clamp comprising a treadle, a pair of toggle members actuated thereby for The stop pin 136, by en 4. The combination with a work support 1 and a work clamp for holding the work against the support, of means for actuating said clamp comprising a toggle one of the links of which is constructed of two members normally free to slide relatively to each other and adapted to be rigidly connected together, means actuated by the other link for causing relative movement of the members of the first toggle link to move the clamp into engagement with the work, means for rigidly connecting said members together to cause the application of pressure by the clamp to the work as the toggle is straightened, and means for actuating the toggle. V 5. The combination with a work support and a work clamp for holding the work against the support, of means for actuating said clamp comprising a toggle one of the links of which is constructed oftwo mem- V bers normally free to slide relatively to each other and adapted to be rigidly connected together, means actuated bythe other link for causing relative movement of the members of the two-part toggle link to move the clamp into engagement with the work, means rendered operative upon the engagement of the clamp with the work for rigidly connecting said members together to cause the application of pressure by the clamp to the work as the toggle is straightened, and means for actuating the toggle.

6. In a machine of the type in which a piece of work is supported in position to be operated upon and a normally retracted work clamp is initially actuated by a light preliminary pressure to bring it into engagement with the work and by a heavy final pressure firmly to hold the work, the combination of a lever for actuating the work clamp; a toggle for actuating said lever comprising an extensible link connected with said lever, said link having two component parts normally free to slide with respect to each otherand adapted to be rigidly connected together, and a second link connected with the extensible link; a treadle for actu ating the toggle; means actuated by said second link as the toggle is straightenedfor lengthening said extensiblelink to cause the clamp to be brought into engagement with the work; and means rendered operative by the engagement of theclamp with the work for rigidly connecting the parts of the extensible link in extended relation during the continued straightening of the toggle to cause the clamp firmly to hold the work.

7. A machine of the class described having, in combination, a work support, a clamp member for holding the work against the support, mechanism for actuating the clamp member comprising a treadle and'means ac.-

tuated directly by the treadle for giving a ing, in combination, a work support, a clamp 7 the toggle is straightened.

member for holding the work against the support, a lever, means constructed and arranged to transmit from the lever to the clamp member a movement relatively great as compared to the movement ofthe lever during the first part of the movement of the lever and other means arranged to co-operate with the first-named means to transmit from the lever to the clamp member amovement relatively small as compared to the movement of the lever during the latter part of the movement of the lever. Y

9. A machine of the class described having, in combination, a work support, a de vice for clamping the work against the support, a lever having a fixed fulcrum, an extensible link pivoted at one end to said lever and at its opposite end to said device and coacting with said lever to constitute a toggle, a treadle connected with said lever for actuating the toggle, means connecting said lever and said link for extending the link during the preliminary straightening movement of the toggle to effect a relatively rapid closing of the clamp member, and means deriving its movement from the treadle for transmitting a direct thrust through said link from its pivotal connec: tion with said lever to said device to effect the application of a relatively heavy pres sure during the final straightening move ment of the toggle.

10. A toggle mechanism having two links one of which comprises two members normally free to slide relatively to each other and adaptedfto be rigidly connected together, means for causing relative movement of said link members during the preliminary straightening movement of the toggle, and means for connecting said members together to cause them to function as a rigid member during the final application of pressurevas 11. A toggle mechanism having two links the first of which comprises two members normally freeto slide relatively to each other and adapted to be rigidly connected together, means actauted by the second link for causing relative movement of the members of the first llnk, and means actuated 'by the second link for connecting said members together to cause them to function as a rigid member during the application of pressure as the toggle is straightened.

12. A toggle mechanism comprising two links the first of which is constructed of two members normally free to slide relatively to each other and adapted to be rigidly connected together, means actuated by the second link for causing relative movement of the parts of the first link during the early part of the straightening of the toggle, and means actuated by the second link to connect the two members of the first link thus causing them to function as a single rigid link during the latter part of the straightening of the toggle to cause the application of pressure during that part of the straightening of the toggle, and means for actuating the toggle.

13. A machine of the class described having a toggle comprising two links one of which is extensible and is made up of two component parts normally free to slide with respect to each other and adapted to be rigidly connected together, means a'ctuated by the other link as the toggle is straightened for lengthening the extensible link, and means rendered operative by the exertion of pressure as the toggle is straightened for thereafter rigidly connecting the parts of the extensible link in extended relation during the continued straightening of the toggle to render the latter capable of exerting pressure. I

14. A machine of the class described, having, in combination, a work support, a treadle, a clamp for holding the work against the support, said clamp deriving motion solely from the treadle, and connec- 'tions between the treadle and the clamp for abruptly increasing the clamping pressure after the clamp engages the work during a gradually increasing application of pressure on the treadle.

15. A machineof the class described having, in combination, a work support, a treadle, a clamping device for holding work against the support, said clamping device deriving motion solely from the treadle, and connecting means between the clamping device and the treadle for first yieldingly and then positively operating said device and constructed and arranged to increase abruptly the clamping stress between successive yielding and positive movements of said device as the treadle is depressed to clamp the work.

GIDEQN JULIAN. 

